A satellite network that has helped save more than 6000 people in United State since 1982 has moved to a new digital system that gives the most reliable, information on the location of aircraft, vessels and people in difficulty. 5 MHz, the signals of an emergency beacon on the weather satellites that are part of Search And Rescue Satellite-Aided Tracking (SARSAT) system. 1, is no longer the National Oceanic And Atmospheric Administration processes 121. The digital signals are transmitted to 5 watts, compared to a fraction of a watt for the analog signal, and c is less noise and interference in the 406 MHz band, reducing the number of false alarms. The new digital signals and to provide more information to determine position to 5 km inside, compared to 18 km for the old, analog signals. Under an international agreement, hours SARSAT 406 MHz only receives signals from Earth-based lighthouses. From February.